Failing example extracted from large files identified by Paul D'Ambra…

… (Posthog) ... see comment from MartinWorkfully: PostHog/posthog-js#1668

packages/rrweb-snapshot/test/css.test.ts

@@ -227,6 +227,46 @@ describe('css splitter', () => {
     expect(splitCssText(cssText, style)).toEqual(sections);
   });
 
+  it('finds css textElement splits correctly, with substring matching going from many to none', () => {
+    const window = new Window({ url: 'https://localhost:8080' });
+    const document = window.document;
+    document.head.innerHTML = `<style>.section-news-v3-detail .news-cnt-wrapper .plugins-wrapper2 :where(figure):not(:where([class~="not-prose"],[class~="not-prose"] *)) {
+    margin-top: 2em;
+    margin-bottom: 2em;
+}
+
+.section-news-v3-detail .news-cnt-wrapper .plugins-wrapper2 :where(.prose > :first-child):not(:where([class~="not-prose"],[cl</style>`;
+    const style = document.querySelector('style');
+    if (style) {
+      style.append(`ass~="not-prose"] *)) {
+    margin-top: 0;
+}
+
+.section-news-v3-detail .news-cnt-wrapper .plugins-wrapper2 :where(.prose > :last-child):not(:where([class~="not-prose"],[class~="not-prose"] *)) {
+    margin-bottom: 0;
+}
+
+.section-news-v3-detail .news-cnt-wrapper .plugins-wrapper2 {
+    width: 100%;
+    overflow-wrap: break-word;
+}
+
+.section-home {
+    height: 100%;
+    overflow-y: auto;
+}
+`);
+
+      const expected = [
+        '.section-news-v3-detail .news-cnt-wrapper .plugins-wrapper2 :where(figure):not(:where([class~="not-prose"],[class~="not-prose"] *)) { margin-top: 2em; margin-bottom: 2em; }.section-news-v3-detail .news-cnt-wrapper .plugins-wrapper2 :where(.prose > :first-child):not(:where([class~="not-prose"],[cl',
+        'ass~="not-prose"] *)) { margin-top: 0px; }.section-news-v3-detail .news-cnt-wrapper .plugins-wrapper2 :where(.prose > :last-child):not(:where([class~="not-prose"],[class~="not-prose"] *)) { margin-bottom: 0px; }.section-news-v3-detail .news-cnt-wrapper .plugins-wrapper2 { width: 100%; overflow-wrap: break-word; }.section-home { height: 100%; overflow-y: auto; }',
+      ];
+      const browserSheet = expected.join('');
+      expect(stringifyStylesheet(style.sheet!)).toEqual(browserSheet);
+      expect(splitCssText(browserSheet, style)).toEqual(expected);
+    }
+  });
+
   it('finds css textElement splits correctly, even with repeated sections', () => {
     const window = new Window({ url: 'https://localhost:8080' });
     const document = window.document;